1. Questions of the Day Convert 15 km to m. Convert 30 km/h to m/s
What do you think density means?
Questions of the Day

2. Kelvin – K (temperature)
Basic Units combine with prefixes to make a final amount
Metric System
Basic SI Units
Meter – m (length)
Gram – g (mass)
Liter – L (volume)
Kelvin – K (temperature)
Common Prefixes
Micro – u 1/
Milli – m 1/1000
Centi – c 1/100
Kilo – k 1000

3. Mass, Volume, & Density

4. Mass There are 3 states of matter: Solid Liquid Gas
Measurement of the amount of matter
(or stuff) in an object
Measured in grams (g)
There are 3 states of matter:
Solid
Liquid
Gas
There are 3 states of matter:
Solid
Liquid
Gas

5. Volume Measurement of the amount of space an object takes up
Measured in milliliters (ml) or cm3

6. Which do you think would have the greater volume? The greater mass? Why?
1 kg of rocks
1 kg of feathers

7. Density
Density is defined as mass per unit volume. It is a measure of how tightly packed and how heavy the molecules are in an object. Density is the amount of matter within a certain volume.
Density is the amount of matter within a certain volume.

8. Which one is more dense? Demonstration: People in a square
How about this: Which square is more dense?

9. Which one is more dense?
Now which one is more dense?

10. Write the density equation
If an object has a mass of 13 g and a volume of 22 mL, what is it’s density?
How is it that cm^3 is the same as a mL? (think about the volume equation)
Questions of the Day AND Get out your notes from yesterday (5 times written) for a grade

11. To find the density 1- Find the mass of the object
2- Find the volume of the object
3- Divide
Density = Mass g
Volume c³
ALWAYS REMEMBER UNITS!

12. Find the mass of the object Find the volume of the object
To find density:
Find the mass of the object
Find the volume of the object
Divide : Density = Mass - Volume
Ex. If the mass of an object is 35 grams and it takes up 7 cm3 of space, calculate the density.

13. Find the mass of the object Find the volume of the object
To find density:
Find the mass of the object
Find the volume of the object
Divide : Density = Mass - Volume
Ex. If the mass of an object is 35 grams and it takes up 7 cm3 of space, calculate the density
Set up your density problems like this:
Given: Mass = 35 grams Unknown: Density (g/ cm3) Volume = 7 cm3
Formula: D = M / V
Solution: D = 35g/7 cm3
D = 5 g/cm3

14. Let’s try some density problems together Work on these problems with your neighbor
1 Frank has a paper clip. It has a mass of 9g and a volume of 3cm3. What is its density?
2. Frank also has an eraser. It has a mass of 3g, and a volume of 1cm3. What is its density?
3. Jack has a rock. The rock has a mass of 6g and a volume of 3cm3. What is the density of the rock?
4. Jill has a gel pen. The gel pen has a mass of 8g and a volume of 2cm3. What is the density of the rock?

15. Change Mass AND Keep Volume Same
Ways to Affect Density
Change Mass AND Keep Volume Same
Increase the mass  increase density Decrease the mass  decrease in density Which container has more density? A B

17. Change Volume AND Keep Mass Same
Ways to Affect Density
Change Volume AND Keep Mass Same
Increase the volume  decrease density Decrease the volume  increase density Which container has more density? A B

18. In your notebook illustrate the answer to the following question: What 2 ways will INCREASE density?

19. What 2 ways will INCREASE density?
Keep the same mass AND decrease the volume
Keep the same volume AND increase the mass

20. Liquid Layers
If you pour together liquids that don’t mix and have different densities, they will form liquid layers.
The liquid with the highest density will be on the bottom.
The liquid with the lowest density will be on the top.
Objects or substances with MORE density will sink below objects or substances with LESS density
Which do you think is MORE dense,
Water or Oil???

21. Water, Oil…and a Superball
The oil is less dense than the water, so it’s on top. The superball is less dense than water, but more dense than oil, so it sinks to the bottom of the oil layer, yet floats on the top of the water layer.

22. If you have 2 or more substances,
the MORE dense substance will be on bottom
The LESS dense substance will be on top

23. Liquid 5 Liquid 3 Liquid 1 Liquid 2 Liquid 4
The density of five liquids are measured as follows:
Liquid 1: 1.0 g/mL
Liquid 2: 1.38 g/mL
Liquid 3: 0.77 g/mL
Liquid 4: 2.95 g/mL
Liquid 5: g/mL
Draw a picture of all 5 liquids in a test tube how they would layer according to density
Liquid 5
Liquid 3
Liquid 1
Liquid 2
Liquid 4

24. Liquid Layers
Check out this picture. Which layer has the highest density?
Which layer has the lowest density?
Imagine that the liquids have the following densities:
10g/cm3. 3g/cm3.
6g/cm3. 5g/cm3.
Which number would go with which layer?
3 g/cm3
5 g/cm3
6 g/cm3
10 g/cm3

25. Liquid Layers – Try with your neighbor
Which liquid has the highest density?
Which liquid has the lowest density?
Which liquid has the middle density?

26. Liquid Layers Try on your own!
Imagine that the liquids on the right have the following densities:
15g/cm g/cm3
3g/cm g/cm3
7g/cm g/cm3
Match the colors to the correct densities.
3g/cm3
7g/cm3
9g/cm3
10g/cm3
12g/cm3
15g/cm3

27. Review What is the formula for density?
What happens if you pour together liquids that have different densities?
Will the liquid on the top have the highest or lowest density?
Will the liquid on the bottom have the highest or lowest density?

28. Super Scientist Question of the Day
Jake has a book, a ruler, and a balance.
How can Jake find the density of the book with the tools he has?

29. Questions of the Day Turn in work to the table by the door.
Convert 7.23 L to mL
Convert 3475 cg to g
What are derived units?
What metric unit of measurement would you use to measure the length of a basketball court?
Questions of the Day Turn in work to the table by the door.

30. Dimensional Analysis (Important for BIG conversions)

31. King Henry Doesn’t Usually Drink Chocolate Milk
k – h – da – UNIT – d – c – m

32. Dimensional Analysis (Important for BIG conversions)
Converting 10 m/s to km/hr

33. Questions of the Day QUIZ at the end of class!
Convert 5.31 cL to L
Convert 7642 g to mg
What is dimensional analysis?
Why is it important we use dimensional analysis? How is it useful?
Questions of the Day QUIZ at the end of class!

34. Significant Figures